The present invention relates to a sorter with an automatic discharging unit wherein sorting information printed on paper sheets (such as mail) is read to sort the paper sheets in corresponding stacking sections, and the paper sheets in each stacking section are automatically discharged and delivered to a subsequent process.
A sorter with an automatic discharging unit has recently been developed which will automatically discharge mail stacked in each stacking section and deliver it to a mailing address card issuing section and a bundling section. Automatic pushout mechanisms (not shown) are disposed in stacking sections b, c and d of a sorter main body a in FIG. 1. When a predetermined amount of postal matter A has been stacked in one of the stacking sections b, c and d, the stack of postal matter A is automatically pushed out in the backward direction by the corresponding automatic pushout mechanism and is transferred to a corresponding one of endless conveyor belts e, f and g which are disposed at the rear side of the sorter main body a and arranged in a vertical order corresponding to rows of stacking sections b, c and d. The stacks are then conveyed on the conveyor belts e, f and g in the horizontal direction. Thereafter, each stack is transferred to an elevator (not shown) and a conveying line (not shown). A mailing address card is then placed on each stack, which is then bundled.
In the case of discharging the postal matter A in a designated stacking section, subsequent postal matter A intended to be stacked in this designated stacking section is stacked in a preliminary stacking section h by a discharging mechanism while the stacked postal matter A in the designated stacking section is discharged, thereby avoiding rejection of the subsequent postal matter A.
However, in the apparatus described above, it is only when a predetermined amount of postal matter (e.g., 10 items) is stacked in the preliminary stacking section h that they are discharged therefrom. For this reason, the preliminary stacking section is exclusively used for the designated stacking section for a long period of time during which it cannot serve any other stacking section. As a result, the amount of rejected postal matter greatly increases, resulting in inconvenience.